【发布时间】：2018-03-26 14:59:53
【问题描述】：
我正在尝试从 firebase 数据库中恢复一个值并将其与 UITextField 值进行比较，如果匹配，我将其保存到我将使用的 var 中。问题是，当我使用它时，有问题的变量有一个默认值。
上面我展示了我的 func 代码，其中受影响的变量是“codeRecovered”：
@IBAction func signUpAction(_ sender: AnyObject)
{
var codeRecovered: String = ""
if emailSignUpTextField.text == "" || self.secretCodeTextField.text == "" {
let alertController = UIAlertController(title: "Error", message: "Please enter your email, pin code and password", preferredStyle: .alert)
let defaultAction = UIAlertAction(title: "OK", style: .cancel, handler: nil)
alertController.addAction(defaultAction)
present(alertController, animated: true, completion: nil)
} else {
self.dbHandler = self.ref?.child("Companies").observe(.value, with: { (snapshot) in
for child in snapshot.children {
let snap = child as! DataSnapshot
let value = snap.value as! [String:String]
if let auxSecretCode = value["secretCode"]
{
if auxSecretCode == self.secretCodeTextField.text{
print("Value recovered OK(works fine): \(auxSecretCode)")
codeRecovered = auxSecretCode
print("Recovered value saved OK(works fine): \(codeRecovered)")
}
}
}
})
//Here codeRecovered is already ""
print("\(codeRecovered) is the recovered value(empty) and \(self.secretCodeTextField.text ?? "def") is the textField value")
if codeRecovered != self.secretCodeTextField.text{
let alertController = UIAlertController(title: "Error", message: "Please enter a correct pin code", preferredStyle: .alert)
let defaultAction = UIAlertAction(title: "OK", style: .cancel, handler: nil)
alertController.addAction(defaultAction)
present(alertController, animated: true, completion: nil)
}
//....
【问题讨论】：
-
没有注意到你有同步我认为问题是默认值，确保对 firebase 的调用有延迟尝试将 ckeck if 语句移动到回调中或将其代码放入函数中叫它